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Re: what does "unb_force" mean in the record file of CohesiveTriaxialTest?


Protosssword a écrit :
> Hi,
> I've just got WallStresses file from CohesiveTriaxialTest. There's a
> column called unb_force, what does this column mean?
> Thank you!
To answer to your question give a look to the source file of the
CohesiveTriaxialTest : CohesiveTriaxialTest.cpp in
trunk/pkg/dem/PreProcessor/. A search about "WallStresses" show you that
"Wallstresses" is in fact the value of the variable
"WallStressRecordFile" of the CohesiveTriaxialTest class : see line 121
(in my recent version) :
WallStressRecordFile = "./WallStresses";
Then this variable WallStressRecordFile is used to define the
"ouptutFile" of the Engine TriaxialStateRecorder :

triaxialStateRecorder =
triaxialStateRecorder-> outputFile = WallStressRecordFile; (around l.627)

So, let's jump to the source files for TriaxialStateRecorder ! You'll
find them in trunk/pkg/dem/Engine/DeusExMachina/ and you'll find in them
how this file ("WallStresses") is filled (the end of the .cpp with
ofile<< ...). So you'll see that in this unb_force column is in fact
written the result of triaxialCompressionEngine->ComputeUnbalancedForce
I'm sure you guessed now that you have to open the source files for
TriaxialCompressionEngine ! They are in the same folder, but to avoid
making a too long mail I tell you right now that in fact
TriaxialCompressionEngine inherits from TriaxialStressController (always
same folder), where this ComputeUnbalancedForce(...) is defined. So give
a look to it (§ Real
TriaxialStressController::ComputeUnbalancedForce(MetaBody * ncb, bool
maxUnbalanced) in the .cpp) and you will know what it is exactly ! The
idea is that parameter could be used to evaluate the state (equilibrium
or not) of the sample by considering the sum of forces acting on each
body of the sample. In a perfect state of equilibrium you will have 0
and in fact values of some % are generally considered satisfying.

Welcome in YADE !!! :-)